According to J. Stuart Russell (The Parousia, 503), the Jewish War of the late 60s AD involved more than Palestine. Slaughter encompassed the empire, wherever Jews were:
“Tacitus speaks of the bitter animosity with which the Arab auxiliaries of Titus were filled against the Jews, and we have a fearful proof of the intense hatred felt towards the Jews by the neighboring nations in the wholesale massacres of that unhappy people perpetrated in many cities just before the outbreak of the war. The whole Jewish population of Caesarea were massacred in one day. In Syria every city was divided into two camps, Jews and Syrians. In Scythopolis upwards of thirteen thousand Jews were butchered; in Ascalon, Ptolemais, and Tyre, similar atrocities took place. But in Alexandria the carnage of the Jewish inhabitants exceeded all other massacres. The whole Jewish quarter was deluged with blood, and fifty thousand corpses lay in ghastly heaps in the streets [according to Josephus, Jewish War, 2.18].”
How many of these slaughtered Jews were disciples of Jesus? We have no way to know, but we do know that the Romans didn’t distinguish the two. According to Sulpitius Severus (The Sacred History), the Romans intended to destroy both Judaism and Christianity when they destroyed the temple:
“Titus is said, after calling a council, to have first deliberated whether he should destroy the temple, a structure of such extraordinary work. For it seemed good to some that a sacred edifice, distinguished above all human achievements, ought not to be destroyed, inasmuch as, if preserved, it would furnish an evidence of Roman moderation, but, if destroyed, would serve for a perpetual proof of Roman cruelty. But on the opposite side, others and Titus himself thought that the temple ought specially to be overthrown, in order that the religion of the Jews and of the Christians might be more thoroughly subverted; for that these religions, although contrary to each other, had nevertheless proceeded from the same authors; that the Christians had sprung up from among the Jews; and that, if the root were extirpated, the offshoot would speedily perish.”
The Romans had not reckoned with the possibility of a religion without a temple. They didn’t reckon with the adaptability of Judaism.